[cbrannam]

I’m having a problem getting my hands around hard turning on our new Captain L370M lathe. The shop is starting to get more and more hard turning jobs coming in. The shop use to give this work to the manual machinist. Well since we laid him off last week, we don’t have that option anymore. So I have to get this under control and learn.

The finial dimensions of the product need to be: They are RC 62 hard.
Dia: 1.760 +0.000
-0.001
Length: 7.875 ±0.030

here is the program that i have but dont know if it is right or not.

N0001 G00 X20 Z20
N0002 G50 S3500
NAT02
N0100 G97 S713 M41 M04
N0101 G00 Z0.100 T030303 (cNMG 432 TP2500 MF5)
N0102 X2.098 (msc# 88443650)
N0103 G96 S361
N0104 X1.774
N0105 G01 Z0.100 F0.008
N0106 Z-7.95 X1.774+0.0000 (TAPER)
N0107 X2.098
N0108 G00 X20 Z20 T0300
N0109 M00
NAT03 (CHANGE "X" OFFSSET OF TOOL #2 TO GET TO 1.760)
N0200 G97 S1013 M41 M04
N0201 G00 Z0.100 T020202 (DNMG 432 KY4400 T0420)
N0202 X2.098 (MSC# 03752516)
N0203 G96 S461
N0204 X1.774
N0205 G01 Z0.100 F0.008
N0206 Z-7.95 X1.774+0.0000 (TAPER)
N0207 X2.098
N0208 G00 X20 Z20 T0200
N0209 M02

[riverrat]

The feed rates look a little high to me, based on my limited knowledge with sumitomo.

.004 per side
.004 feedrate
400 sfpm

I might be all wet on some of that, if so enlighten me.
I like to learn.

[fizzissist]

You laid off your manual machinist who knew how to do it. Now you're stuck learning it.

Maybe your former manual machinist would like to pop in here and offer free help. Meanwhile, after looking at your program, I think you should run it and see what happens.

[Rally]

You laid off your manual machinist who knew how to do it. Now you're stuck learning it.

Maybe your former manual machinist would like to pop in here and offer free help. Meanwhile, after looking at your program, I think you should run it and see what happens.

I am rolling now! Thank you that made my day.

[uli12us]

I can see what happens, you make much scrap. I don't have much experience with hard turning, but the speeds seems very high. And you have the false tools. You need a CBN tool who's a bad heat-conductor. The hardened steel must heat to a temperature above the hardening temp. In my first job I have sometimes worked on surface heated parts, at this times I worked with a K01 cutting plate. Today there are several much better tools for this work, some sorts of CBN or, for non iron workpieces diamond tools as well.